Surface finishing machine



A. P. ROBINSON SURFACE FINISHING MACHINE July 22, 1952 Filed March 28, 1950 2 Sl-IEETS-SHEET l w/ w v W ,1. w a kvla &

l/vuz/vroz HLBERT P. Poem/Jaw July 22, 1952 A. P. ROBINSON 2,603,919

SURFACE FINISHING MACHINE Filed March 28, 1950 2 SHEETS-SHEET 2 l/vuz-w r02 141.5527 P. Poe N60 HTTOENEYJ' Patented July 22, 1952 OFFICE SURFACE FINISHING MACHINE 'Albert P. Robinson, Seattle, Wash. Application March 28, 1950, Serial No. 152,399

v This invention relates chines of those kinds now quite generally used for the grinding and finishing of floor surfaces, base moldings, stairs, etc., that are made of terrazzo, cement and like materials. More particularly the present invention has to do with the provision and use of means, which might be applied as attachments, on a common type of hand supported motor driven grinding machine designed to aid in the support and guidance of the machine in its ordinary uses.

It is the principal object of this invention to provide, in connection with a grinding machine of the above kind, a guide and guard means that can be engaged in rolling or sliding contact with a side surface, such as a base molding, stair riser 3 Claims. (Cl. 51-477) to improvements in maor side wall, to limit the extent toward which the guiding arms, and roller equipped supports on.

hand operated grinding machines designed to protect surfaces against being grooved, gouged or marred by the grinding disk to relieve the user of the weight of the machine and strain required to be exerted to hold it level or otherwise properly handle it, and to insure more satisfactory work being done.

It is also an object to provide simplified'and practical means for mounting the grinding and supporting means on the, grinding machine.

In accomplishing these and other objects of the invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings, where- Fig.- 1 is a perspective view of a common type of hand supported floor surfacing or grinding machine, equipped with adjustable supports and guides embodied by the present invention.

Fig. 2 is a plan view of the machine, with apart of the head broken away for purpose of better understanding; this viewillustrating particularly the guiding and gauging functions of the head attachment.

Fig. 3 is a side view of the machine as shown in Fig. 2, particularly illustrating the manner of supporting the machine for ordinary fioor grind ing work. I

Fig. 4 is a front end view of the machine as I turned to a position for surfacing a base molding or other vertical surface.

Fig. 5 is a rear end view of the machine as seen in Fig. 4.

Fig. 6 is an enlarged, horizontal section through the head of the machine, as on line 5-6 in Fig.

3, showing the means for attachment guiding and gauging rollers.

Fig. 7 is a cross-section on line in Fig. 6.

Referring more in 'detail to the drawings l0 designates, in its entirety, a common type of grinding machine now generally used for the grinding and surface finishing of terrazzo floors, base moldings, and the like. It comprises an electric motor, not shown, enclosed within a cylindrical housing [2, to'the forward end of which housing is secured a, gear case or housing l3 from which'a motor driven shaft 14 extends, and which shaft mounts a grinding or surfacing disk l5 thereon. The shaft I4 is mounted at aright angle to the axial line of the motor housing, and the grinding disk I 5 is of that kind generally used for floor grinding purposes and usually is made of carborundum. Disks used might assume other forms than that shown, but regardless of form, would be operated and used in the same or substantially the same manner as has been illustrated.

At the rearyend of the housing I2 is a tubular, axial extension or. handle l8 through which the electric circuit wires lead to the motor. A cable containing the circuit wires is designated at 20. The gear housing [3 is formed at opposite sides with threaded holes as at 2| in Fig. 1, into one or the other of, which a handle, as at 22 in Fig. .1, may be threaded. In the ordinary use of the machine, the operator grasps the handles and 22, and holds the machine in such position that the face of the disk l5 flatly engages the surface that is to be smoothed or ground. I

Due to the weight'of the machine and manner in which it is required to be used, it is diflicult and tiring to handle with accuracy. It is essential that the grinding disk be held flatly against the surface being worked on, and that it shall not be gouged into the base moldings. Therefore, it has been the object of the invention to provide means for positively limiting the distance to which the disk l5 can approach the baseboard when the machine is used as in Fig. 3, and also to provide adjustable supports for the machine to relieve the operator of the machines weight, sothat work is made easier and. therefore can be better accomplished.

As shown best in Figs. 2 and 3, the present guidingand gaugingmeans are applied to the gear housing I 3. This housing, as seen in 3, has a cylindrically shaped, downwardly opening neck I302, over the lower end of which a disk 25 is fixedby a plurality of screw bolts 26, as has been shown best in Fig. '7. The shaft M by which of the the grinder disk [5 is mounted extends centrally 3 through disk 25. The periphery of the disk 25 extends slightly beyond the periphery of neck Br, and fitted rotatably thereabout is a ring 28. This ringis held in place and for rotation by two pairs of U-shaped clips, 29 and 30. Clips of the 5 same pair are applied at diametrically opposite points and are secured by screws 3| that are passed through the leg portions of the clips and ring. The inner end portion of the legs of the clips overlapitop and bottom faces of the edge of the disk thus to retain that relationship of ring 28 and disk 25 shown in Fig. '7. The U- shaped clips 29 are relatively small, while the clips 30, which are spaced 90 from clips: 20 are relatively large and their base portions extend 1 well beyond the ring 28 to provide-parts to-se'rve as mounting bearings for paired guiding-and supporting arms 3434 which are well shown in Figs. 2 and 4 as serving these functions.

The arms 3434 are in the form of straight baits;'jslidably contained inthe clips -30; for-2e):- tension or retractiona1Theyqextend ,fronroppositessidest of thehead .1 3substantially in?the same direction; "and at their putter endsare preferably equipped: with. rollerswdflw-or. "Wifih'tfiflilifiblli'rfikidS designed to engageinrcontactwith .a basesurfaee when the: machme-;.isi used Fas-in--Fig, v3 ,orfto engageimsupportingeontaet with armor-surface whenthemchine'iisusedas-infigrie The arms" 3 4=-3tareadapted :to ihesfialned. disfierentmositions :of adjustment spring glateh' clips .5! having: endscsecured to ":thGfiC'fiPS" HI 39: and: then: opposite rendsiturned downwardly; as seei'rzat 4.1 infigcfi: to engageiirr notchesilt :that are formed :alongrthei'armsz of is. made rhyiniereiy 'zdiseng'agingetli'eilip .4 1' therefrom then the? arnnto ea". desired position; and then releasing... the; lockingzrclips form's-Seating iinzonenif .the:.notches ski-hereof: Thev arms 34- 34 I are nsedzprimarily to: prevent the base moldings being..-'gongeri.1m marredb'ysthe. grinding disk. It is possible to adjust thesearnrs softh'a't both can mamitained- .in-irol'lhrgf contact witha base molding; Fig. whileifire: operator moyes the maehine--back-:andiforth:.

In- -order to. hold the grinding disk level tzith a; floor surf-ace a n'd r el iew'e *themperaitor ftl'ie weight' o'f -the:machine,-' That/e equipped the 'outer end-of the I housing 14' 2 with adjustable supports: Theseai'ewell shownin Figs. l and-3? For-their mounting, Iiappl-y-a-strap orband m ti'g'h tly about housing I? and' sec-ure its endstogether by means of 'a clamp belt ii l to the band at opposite sides of the ma'chine, are tubular bean ings52 52, and slidably adjustable withm these are-legs 53--'53:whih preferably are equipped at their lower ends witli' supporting rcillersSfl-M; Sfet screws=55 are th readezit into tnea eanngstz to engage thelegs-to secure them at positions to Which-they'maybe adjusted: It is the intenttlfat theflegs tfljsliall coactjwith {the- -disk 15 for support of the machine, "'andfshall{operate'toretain the "machine-in- 'a'leve'lposition', ,ashas been ined'by i 4 'Ifzitis desired to minda' vertical b'asesurface, the; machineisi turned on its "side; asito theposition ofFigs. 4 and 5. In this position the gaugingarms 34-.34 areturned'to pbsition' toserve as supports for the machine and they are supplemented by a supporting leg SG 110631366. at the fonterendof the machine. A.-1eg-v 5511's slid'ably adjustable for. extension. or. retraction in a bearing 57 fixed-tetherbandit].' This ;leg. ex'tends at ahri ht angle to the supportinglegs Mend (it canbe reversed-inthebearing157-.so as-.to=be ex- 75 tended to either side of the machine. A set screw 60 is threaded into the bearing 51 to engage and secure the leg 56 at any position of adjustment. At its outer end the leg mounts a roller 62 for rolling contact with a supporting surface. It will be understood that when the machine is being used as in Fig. 5, this leg engages the vertical or side surface to maintain the grinding disk in proper relationship to the surface being workedrom While thesarrns '343:'4" are;at that time used'as shown in Fig: 4; to supportthe forward end of the machine. The other end of the machine, at this time, is supported by the legs 53e-'5:3,;as shown in Fig. 5.

The present type of machine is thus characterized by -the application thereto of supports andguides thatserve to support the machine in a level working position, and to insure against gouging; grooving or otherwise causing the surfaces worked on to be marred. The adlustably mounted terms; 134-44 serveeas-sin Fi 3; jtodeflnitely' liinit (the approach of.- the disk: It. towardthe: base: or-s'ide; i'surface; Dueyto; thesrfaet that theermsr. mermountedsaon.azring-that rotatable: about. thegnxis: of *the. nee-k I31: grinder. shaft M; as inLFig; 2, .t-hesmachine; rasped: by handles lfiza-nd: 22., :can :be oscillated back zand'ffor th the rollersi lllin rolling tact with ;=the basexorrother siderwallisurface;

The Tadj-ustability of: the: 34-34;, vlegs 5353 and 56, provides forrtaking'care lofivaris ous. sizes and types 1:01". igrlindingzdisksg Thermalin advantage, however; residesin anaesworkman roan-speed work stithoutxlanger of :causing damage to tsuriaces. andwithout'zeaussing any extraeffiort-"for supportwor *grindingzof themachine; I

In the-use of the term grinding: diskms used: in theclaims whi'tih terminate this'specifination, I intend'ito include'grinding disks or. heads of Wart ous kinds: and shapes; the-use of which are not inconsistent withthe invention as hereindescribed; V

Having thus 'des'cribed my invention, what l' claim as new" therein a and desire to secure hy Letters Patent, is: I

1. Aihand portablemachine of the character described comprising a motor housingga mo tor driven shaft -extended'therefrom; a' grinding disk mounted on "the shaft "tofi-atly engagea surface to be finished thereby, a ring 0 flessen-diameter thanthedisk mounted on-the'housing "for free rotation, coaxially-of the "disk-mounting shaft-and closely adjacent thetopside of the "disk; a

e of arms mountedonthe ring at opposite-sides of the shaft and extended therefrom beyondthe peripheryof the disk at one side thereof, and rollers-mountediat the outer" ends of the arms; said armbeing arranged to serve as wheeled-supports forith'e machine when used-for su'rfaeing a side wall surface, and to serve-as-guiding-and guarding means for aside wall surface when-usedfor surfacing a floor adjacentsaid side wall surface.

2. A floor surfacing machine of thecharacter described comprising'a motel-housing; equipped with handles for .thefunctional manipulationof the machine in use, a motor driven'shaftextended downwardly from .the housing atoneen-dthereof, a grinding disk mounted on thejshaft end to flatly engage a floorsurface, a collar of substantially lesser diameter than the. grinding disk rotatably fitted to the housing immediately above the disk andcoaxially thereof; armsadjust'ably'fixed .to thecollar' attopposi'te side's-and extended therefrom in spaced relationship and in the same general direction and beyond the periphery of the disk at the same side thereof to engage at their ends with a side wall surface as a means of limiting the approach toward the wall of that portion of the periphery of the disk that is between the ends of the said arms.

3. A surfacing machine as recited in claim 2 wherein a clamping band is applied about the end of the housing opposite that mounting the disk, and supports are extended therefrom to support the machine for easy movement on a floor surface and retain the working position of the disk surface, said clamping band being rotatably adjustable about the housing and said supports extend therefrom at opposite sides of the housing ALBERT P. ROBINSON.

, 6 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Fargo June 6, 1950 

